US4647700A - Process for the preparation of meta-chloroanilines - Google Patents
Process for the preparation of meta-chloroanilines Download PDFInfo
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- US4647700A US4647700A US06/780,212 US78021285A US4647700A US 4647700 A US4647700 A US 4647700A US 78021285 A US78021285 A US 78021285A US 4647700 A US4647700 A US 4647700A
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- 238000000034 method Methods 0.000 title claims abstract description 34
- 238000002360 preparation method Methods 0.000 title abstract description 5
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical compound I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 claims abstract description 24
- 229910000043 hydrogen iodide Inorganic materials 0.000 claims abstract description 16
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 9
- 239000001257 hydrogen Substances 0.000 claims abstract description 9
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 5
- 238000006243 chemical reaction Methods 0.000 claims description 35
- 125000001309 chloro group Chemical group Cl* 0.000 claims description 24
- 229910052801 chlorine Inorganic materials 0.000 claims description 20
- 125000004432 carbon atom Chemical group C* 0.000 claims description 18
- UQRLKWGPEVNVHT-UHFFFAOYSA-N 3,5-dichloroaniline Chemical group NC1=CC(Cl)=CC(Cl)=C1 UQRLKWGPEVNVHT-UHFFFAOYSA-N 0.000 claims description 14
- PNPCRKVUWYDDST-UHFFFAOYSA-N 3-chloroaniline Chemical compound NC1=CC=CC(Cl)=C1 PNPCRKVUWYDDST-UHFFFAOYSA-N 0.000 claims description 12
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 12
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims description 12
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 claims description 8
- 239000002253 acid Substances 0.000 claims description 7
- 239000011541 reaction mixture Substances 0.000 claims description 7
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 claims description 5
- 239000000460 chlorine Substances 0.000 claims description 5
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Substances ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 claims description 5
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 claims description 5
- 239000002904 solvent Substances 0.000 claims description 5
- 229910000041 hydrogen chloride Inorganic materials 0.000 claims description 4
- 239000007788 liquid Substances 0.000 claims description 4
- 239000003960 organic solvent Substances 0.000 claims description 4
- 239000012736 aqueous medium Substances 0.000 claims description 3
- 125000005843 halogen group Chemical group 0.000 claims description 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims description 2
- 125000003545 alkoxy group Chemical group 0.000 claims 6
- 125000000217 alkyl group Chemical group 0.000 claims 6
- 125000000951 phenoxy group Chemical group [H]C1=C([H])C([H])=C(O*)C([H])=C1[H] 0.000 claims 4
- 239000007795 chemical reaction product Substances 0.000 claims 2
- 101150108015 STR6 gene Proteins 0.000 claims 1
- MVPPADPHJFYWMZ-IDEBNGHGSA-N chlorobenzene Chemical group Cl[13C]1=[13CH][13CH]=[13CH][13CH]=[13CH]1 MVPPADPHJFYWMZ-IDEBNGHGSA-N 0.000 claims 1
- 239000000543 intermediate Substances 0.000 abstract description 8
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 239000003905 agrochemical Substances 0.000 abstract 1
- 239000011949 solid catalyst Substances 0.000 abstract 1
- PBKONEOXTCPAFI-UHFFFAOYSA-N 1,2,4-trichlorobenzene Chemical compound ClC1=CC=C(Cl)C(Cl)=C1 PBKONEOXTCPAFI-UHFFFAOYSA-N 0.000 description 9
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 9
- 239000000203 mixture Substances 0.000 description 9
- YTDHEFNWWHSXSU-UHFFFAOYSA-N 2,3,5,6-tetrachloroaniline Chemical class NC1=C(Cl)C(Cl)=CC(Cl)=C1Cl YTDHEFNWWHSXSU-UHFFFAOYSA-N 0.000 description 8
- 239000002609 medium Substances 0.000 description 8
- GBKZRUCVLTWAML-UHFFFAOYSA-N 2,3,4,5-tetrachloroaniline Chemical compound NC1=CC(Cl)=C(Cl)C(Cl)=C1Cl GBKZRUCVLTWAML-UHFFFAOYSA-N 0.000 description 7
- BRPSAOUFIJSKOT-UHFFFAOYSA-N 2,3-dichloroaniline Chemical class NC1=CC=CC(Cl)=C1Cl BRPSAOUFIJSKOT-UHFFFAOYSA-N 0.000 description 7
- -1 alkyl radical Chemical class 0.000 description 7
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 6
- 229910052740 iodine Inorganic materials 0.000 description 6
- 239000011630 iodine Substances 0.000 description 6
- MOTBXEPLFOLWHZ-UHFFFAOYSA-N 2,3,5-trichloroaniline Chemical compound NC1=CC(Cl)=CC(Cl)=C1Cl MOTBXEPLFOLWHZ-UHFFFAOYSA-N 0.000 description 5
- SDYWXFYBZPNOFX-UHFFFAOYSA-N 3,4-dichloroaniline Chemical class NC1=CC=C(Cl)C(Cl)=C1 SDYWXFYBZPNOFX-UHFFFAOYSA-N 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- RFFLAFLAYFXFSW-UHFFFAOYSA-N 1,2-dichlorobenzene Chemical compound ClC1=CC=CC=C1Cl RFFLAFLAYFXFSW-UHFFFAOYSA-N 0.000 description 3
- XOGYQVITULCUGU-UHFFFAOYSA-N 3,4,5-trichloroaniline Chemical compound NC1=CC(Cl)=C(Cl)C(Cl)=C1 XOGYQVITULCUGU-UHFFFAOYSA-N 0.000 description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 150000001448 anilines Chemical group 0.000 description 3
- 239000003054 catalyst Substances 0.000 description 3
- DQNOIKMHTBFYTD-UHFFFAOYSA-N n,n,2,3-tetrachloroaniline Chemical compound ClN(Cl)C1=CC=CC(Cl)=C1Cl DQNOIKMHTBFYTD-UHFFFAOYSA-N 0.000 description 3
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- DTQVDTLACAAQTR-UHFFFAOYSA-N Trifluoroacetic acid Chemical compound OC(=O)C(F)(F)F DTQVDTLACAAQTR-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000003849 aromatic solvent Substances 0.000 description 2
- 238000004587 chromatography analysis Methods 0.000 description 2
- 238000004821 distillation Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000007791 liquid phase Substances 0.000 description 2
- KUDPGZONDFORKU-UHFFFAOYSA-N n-chloroaniline Chemical class ClNC1=CC=CC=C1 KUDPGZONDFORKU-UHFFFAOYSA-N 0.000 description 2
- 239000012074 organic phase Substances 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- 239000012429 reaction media Substances 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- KHCZSJXTDDHLGJ-UHFFFAOYSA-N 2,3,4,5,6-pentachloroaniline Chemical compound NC1=C(Cl)C(Cl)=C(Cl)C(Cl)=C1Cl KHCZSJXTDDHLGJ-UHFFFAOYSA-N 0.000 description 1
- AFVFQIVMOAPDHO-UHFFFAOYSA-N Methanesulfonic acid Chemical compound CS(O)(=O)=O AFVFQIVMOAPDHO-UHFFFAOYSA-N 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- 101100386054 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) CYS3 gene Proteins 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 239000012868 active agrochemical ingredient Substances 0.000 description 1
- 125000001931 aliphatic group Chemical group 0.000 description 1
- 229910001516 alkali metal iodide Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000008346 aqueous phase Substances 0.000 description 1
- 150000004982 aromatic amines Chemical class 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000010908 decantation Methods 0.000 description 1
- 238000006298 dechlorination reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- PNDPGZBMCMUPRI-UHFFFAOYSA-N iodine Chemical compound II PNDPGZBMCMUPRI-UHFFFAOYSA-N 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- KUWAAZMPJBFLEO-UHFFFAOYSA-N n,n,2-trichloroaniline Chemical class ClN(Cl)C1=CC=CC=C1Cl KUWAAZMPJBFLEO-UHFFFAOYSA-N 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- KHUXNRRPPZOJPT-UHFFFAOYSA-N phenoxy radical Chemical compound O=C1C=C[CH]C=C1 KHUXNRRPPZOJPT-UHFFFAOYSA-N 0.000 description 1
- 150000003254 radicals Chemical class 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000000638 solvent extraction Methods 0.000 description 1
- 101150035983 str1 gene Proteins 0.000 description 1
- 239000001117 sulphuric acid Substances 0.000 description 1
- 235000011149 sulphuric acid Nutrition 0.000 description 1
- JOXIMZWYDAKGHI-UHFFFAOYSA-N toluene-4-sulfonic acid Chemical compound CC1=CC=C(S(O)(=O)=O)C=C1 JOXIMZWYDAKGHI-UHFFFAOYSA-N 0.000 description 1
- YNJBWRMUSHSURL-UHFFFAOYSA-N trichloroacetic acid Chemical compound OC(=O)C(Cl)(Cl)Cl YNJBWRMUSHSURL-UHFFFAOYSA-N 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C211/00—Compounds containing amino groups bound to a carbon skeleton
- C07C211/43—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton
- C07C211/44—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to only one six-membered aromatic ring
- C07C211/45—Monoamines
- C07C211/46—Aniline
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/68—Preparation of compounds containing amino groups bound to a carbon skeleton from amines, by reactions not involving amino groups, e.g. reduction of unsaturated amines, aromatisation, or substitution of the carbon skeleton
- C07C209/74—Preparation of compounds containing amino groups bound to a carbon skeleton from amines, by reactions not involving amino groups, e.g. reduction of unsaturated amines, aromatisation, or substitution of the carbon skeleton by halogenation, hydrohalogenation, dehalogenation, or dehydrohalogenation
Definitions
- the present invention relates to a process for the preparation of anilines substituted by chlorine in the meta position, by the dechlorination of more highly chlorinated aromatic amines.
- These meta-chloroanilines are intermediates, in particular for the manufacture of agrochemical active ingredients.
- the object of the present invention is to prepare meta-substituted chloroanilines by the selective removal of chlorine atoms by an even simpler method which is therefore easier to carry out industrially.
- the invention relates more particularly to a process for the preparation of anilines substituted in the meta position by chlorine, of the general formula: ##STR1## in which: X' and X", which are identical or different, each represent a chlorine atom, an alkyl radical containing from 1 to 4 carbon atoms or an alkoxy radical containing from 1 to 4 carbon atoms, at least one of the symbols X' and X" necessarily being a chlorine atom and it also being possible for one of the symbols X' and X" to be a hydrogen atom, and
- R', R" and R"' which are identical or different, each represent a chlorine atom, an alkyl radical containing from 1 to 4 carbon atoms, an alkoxy radical containing from 1 to 4 carbon atoms or a phenyl, benzyl or phenoxy radical, it being possible for the phenyl nucleus of these radicals to be substituted by at least one halogen atom, in particular a chlorine atom, an alkyl radical containing from 1 to 4 carbon atoms or an alkoxy radical having 1 to 4 carbon atoms, it being possible for at most two of them to be a hydrogen atom, by reacting a polychloroaniline of the general formula: ##STR2## in which X', X", R', R" and R"' have the same meanings as above, with the additional proviso that at least one of the symbols R', R" and R"' represents a chlorine atom, with hydrogen iodide, in the liquid phase, according to the equation:
- n is an integer from 1 to 3, representing the number of chlorine atoms to be removed per mol of the polychloroaniline A.
- the amount of hydrogen iodide which must be used in the reaction is at least the stoichiometric amount and preferably an excess, i.e. the molar ratio (HI/n) is generally between 2/1 and 20/1 and preferably between 2/1 and 10/1.
- the reaction is carried out either in an aqueous medium, in which case the hydrogen iodide is used in the form of a solution of hydriodic acid, or in an organic medium in an organic solvent which is inert under the reaction conditions and, in particular, towards the hydrogen iodide used and the iodine produced and also towards the hydrogen chloride, such as e.g. an aromatic solvent like toluene or xylene, a chlorinated aromatic solvent like a chlorobenzene, or a chlorinated aliphatic solvent.
- an aromatic solvent like toluene or xylene
- a chlorinated aromatic solvent like a chlorobenzene
- a chlorinated aliphatic solvent such as e.g. an aromatic solvent like toluene or xylene, a chlorinated aromatic solvent like a chlorobenzene, or a chlorinated aliphatic solvent.
- a strong acid can advantageously be added to the reaction medium; it is either a mineral acid such as hydrochloric acid or sulphuric acid, when the reaction is carried out in an aqueous medium, or an organic acid such as acetic acid, trichloroacetic acid, trifluoroacetic acid, methanesulphonic acid or para-toluenesulphonic acid, when the reaction is carried out in an organic solvent medium.
- a mineral acid such as hydrochloric acid or sulphuric acid
- an organic acid such as acetic acid, trichloroacetic acid, trifluoroacetic acid, methanesulphonic acid or para-toluenesulphonic acid
- the hydrogen iodide can either be used as such or be formed in situ under the reaction conditions, e.g. from a mixture of an alkali metal iodide and hydrochloric acid.
- the pressure of the latter increases: there is no disadvantage in carrying out the reaction under autogenous pressure, but it is preferred industrially to limit the pressure to at most 100 bars and preferably to at most 50 bars. To do this, the reaction is carried out under a stream of HI with continuous removal of the HCl formed.
- the reaction temperature is generally between 90° and 250° C. and preferably from 110° to 220° C. At lower temperatures, the reaction is slow and, furthermore, the amine hydroiodides are not completely soluble in the medium. Above 100° C., the medium is homogeneous and the reaction takes place with a virtually quantitative yield, the temperature increase having the effect of accelerating the reaction. Furthermore, it is no longer industrially advantageous to carry out the reaction above 250° C.
- the process according to the invention can be carried out continuously or batchwise.
- the meta-chloroaniline obtained can be separated off by any means which is in itself known, e.g. by solvent extraction and/or by distillation.
- the process according to the invention makes it possible selectively to obtain meta-chloroanilines under conditions which are particularly advantageous for its industrial use, since the reaction is carried out in a completely homogeneous medium, without a catalyst and at very moderate pressures.
- 2,3,4,5-Tetrachloroaniline (0.1 mol) and an aqueous solution containing 8 mol/liter of hydriodic acid (50 ml) are introduced into a pressure-resistant tantalum-lined reactor of 200 cc capacity.
- the mixture is heated for 16 hours at 135° C. under autogeneous pressure, with stirring.
- Example 1 The procedure of Example 1 is followed with modification of the concentration of tetrachloroaniline (2,3,4,5-TTCA), the concentration of hydriodic acid (HI), the temperature (T) and the duration, hydrochloric acid (HCL) being added as the strong acid in two cases.
- Example 1 The procedure of Example 1 is followed, the 2,3,4,5-tetrachloroaniline being replaced by 2,3,5,6-tetrachloroaniline (0.05 mol) and the mixture being heated for 5 hours. It is found that, under these conditions, the degree of conversion of the 2,3,5,6-tetrachloroaniline is 96%, the actual yield of 3,5-dichloroaniline is 81.2%, and 14.7% of unconverted intermediate 2,3,5-trichloroaniline remains.
- Example 1 The procedure of Example 1 is followed, the 2,3,4,5-tetrachloroaniline being replaced successively by 3,4-dichloroaniline and 2,3-dichloroaniline, n being equal to 1 in these cases, each at a concentration of 2 mol/liter, the hydriodic acid being at a concentration of 8 mol/liter, the temperature being 135° C. and the duration being 5 hours.
- the mixture is heated under autogenous pressure for 2 hours at 170° and 210° C. respectively.
- 2,3,4,5-Tetrachloroaniline (0.06 mol) and 2,3,5,6-tetrachloroaniline (0.06 mol) are introduced, together with 1,2,4-trichlorobenzene (100 ml), into a 250 cc glass round-bottomed flask.
- the mixture is stirred and heated to 160° C.
- a stream of dry gaseous hydrogen iodide. is passed through at a rate of 18 to 20 g/hour, with stirring, the temperature being kept at 160° C.
- the gaseous effluent is collected in a bubbler containing water.
- reaction is stopped after 4 hours 20 minutes by shutting off the stream of gaseous hydrogen iodide. 80.5 g of the latter have been used.
- the contents of the reactor are then cooled and neutralised with a dilute aqueous solution of sodium hydroxide, and the organic phase is analysed by gas chromatography. It is found that the degree of conversion of the tetrachloroanilines is 99.5% and that the yield of 3,5-dichloroaniline is 98.1%. 0.9% of trichloroanilines, formed as intermediates in the conversion, remains.
- 1,2-Dichlorobenzene 100 ml
- 2,3-dichloroaniline (0.168 mol)
- 3,4-dichloroaniline 0.072 mol
- the mixture is heated to 160° C. and gaseous hydrogen iodide (0.66 mol; i.e. 2.75 mol of HI per mol of DCA) is passed in over a period of 4 hours, the reaction mixture being stirred.
- reaction mixture is cooled and treated in a conventional manner (as described in the previous examples), and analysis by vapour phase chromatography shows that the degree of conversion of the dichloroanilines is 96.5% and the yield of 3-chloroaniline is 100% relative to the dichloroanilines converted.
- the iodine formed is recovered quantitatively.
- the excess hydrogen iodide is also recovered in the form of iodine, after oxidation with hydrogen peroxide in an acid medium.
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
This invention relates to a process for the preparation of meta-chloroanilines. Polychloroanilines containing at least one chloroatom in the meta position are reacted with hydrogen iodide in a homogeneous aqueous or organic medium at a temperature between about 90° and 250° C. Gaseous hydrogen and solid catalysts are not required. The meta-chloroanilines are useful in the manufacture of agrochemical intermediates.
Description
This application is a continuation of application Ser. No. 518,968, filed 08/01/83, now abandoned.
The present invention relates to a process for the preparation of anilines substituted by chlorine in the meta position, by the dechlorination of more highly chlorinated aromatic amines. These meta-chloroanilines are intermediates, in particular for the manufacture of agrochemical active ingredients.
Numerous processes have already been proposed for the preparation of anilines chlorinated in the meta position, by the hydrodechlorination of polychloroanilines with hydrogen under pressure, in a liquid medium, in the presence of a strong acid and a catalyst based on a noble metal. These processes require high pressures, which, in association with relatively high temperatures and acidic conditions, make it necessary to carry out the reactions in an autoclave, giving rise to serious corrosion problems. Attempts have been made to moderate the temperature and pressure by carrying out the reactions in the presence of iodine-based derivatives, but heterogeneous metal catalysts always have to be used.
The object of the present invention is to prepare meta-substituted chloroanilines by the selective removal of chlorine atoms by an even simpler method which is therefore easier to carry out industrially.
The invention relates more particularly to a process for the preparation of anilines substituted in the meta position by chlorine, of the general formula: ##STR1## in which: X' and X", which are identical or different, each represent a chlorine atom, an alkyl radical containing from 1 to 4 carbon atoms or an alkoxy radical containing from 1 to 4 carbon atoms, at least one of the symbols X' and X" necessarily being a chlorine atom and it also being possible for one of the symbols X' and X" to be a hydrogen atom, and
R', R" and R"', which are identical or different, each represent a chlorine atom, an alkyl radical containing from 1 to 4 carbon atoms, an alkoxy radical containing from 1 to 4 carbon atoms or a phenyl, benzyl or phenoxy radical, it being possible for the phenyl nucleus of these radicals to be substituted by at least one halogen atom, in particular a chlorine atom, an alkyl radical containing from 1 to 4 carbon atoms or an alkoxy radical having 1 to 4 carbon atoms, it being possible for at most two of them to be a hydrogen atom, by reacting a polychloroaniline of the general formula: ##STR2## in which X', X", R', R" and R"' have the same meanings as above, with the additional proviso that at least one of the symbols R', R" and R"' represents a chlorine atom, with hydrogen iodide, in the liquid phase, according to the equation:
A+2nHI→B+nI.sub.2 +nHCl,
in which n is an integer from 1 to 3, representing the number of chlorine atoms to be removed per mol of the polychloroaniline A.
The amount of hydrogen iodide which must be used in the reaction is at least the stoichiometric amount and preferably an excess, i.e. the molar ratio (HI/n) is generally between 2/1 and 20/1 and preferably between 2/1 and 10/1.
The reaction is carried out either in an aqueous medium, in which case the hydrogen iodide is used in the form of a solution of hydriodic acid, or in an organic medium in an organic solvent which is inert under the reaction conditions and, in particular, towards the hydrogen iodide used and the iodine produced and also towards the hydrogen chloride, such as e.g. an aromatic solvent like toluene or xylene, a chlorinated aromatic solvent like a chlorobenzene, or a chlorinated aliphatic solvent.
To accelerate the reaction, a strong acid can advantageously be added to the reaction medium; it is either a mineral acid such as hydrochloric acid or sulphuric acid, when the reaction is carried out in an aqueous medium, or an organic acid such as acetic acid, trichloroacetic acid, trifluoroacetic acid, methanesulphonic acid or para-toluenesulphonic acid, when the reaction is carried out in an organic solvent medium.
Of course, the hydrogen iodide can either be used as such or be formed in situ under the reaction conditions, e.g. from a mixture of an alkali metal iodide and hydrochloric acid.
Furthermore, in an organic medium, as the reaction releases hydrogen chloride, the pressure of the latter increases: there is no disadvantage in carrying out the reaction under autogenous pressure, but it is preferred industrially to limit the pressure to at most 100 bars and preferably to at most 50 bars. To do this, the reaction is carried out under a stream of HI with continuous removal of the HCl formed.
The reaction temperature is generally between 90° and 250° C. and preferably from 110° to 220° C. At lower temperatures, the reaction is slow and, furthermore, the amine hydroiodides are not completely soluble in the medium. Above 100° C., the medium is homogeneous and the reaction takes place with a virtually quantitative yield, the temperature increase having the effect of accelerating the reaction. Furthermore, it is no longer industrially advantageous to carry out the reaction above 250° C.
As compounds of the formula A which can be used to carry out the process, there may be mentioned, in particular, those in whose formulae R', R" and R"' represent a hydrogen or chlorine atom, i.e. 2,3,4,5-, 2,3,4,6- and 2,3,5,6-tetrachloroanilines and also pentachloroaniline, preference being given to 3,4- and 2,3-dichloroanilines, 3,4,5-trichloroaniline and 2,3,4,5- and 2,3,5,6-tetrachloroanilines.
Amongst the meta-chloroanilines of the formula B which can be prepared by the process according to the invention, there may be mentioned, in particular, those in whose formulae R', R" and R"' represent a hydrogen or chlorine atom, i.e. 2,3-, 2,5- and 3,4-dichloroanilines, 2,3,4-, 2,3,5-, 2,3,6-, 2,4,5- and 3,4,5-trichloroanilines and, preferably, 3-chloroaniline and 3,5-dichloroaniline. These chloroanilines can be obtained either by themselves or in mixtures, depending on the starting composition and the degree of conversion.
The process according to the invention can be carried out continuously or batchwise. At the end of the reaction, the meta-chloroaniline obtained can be separated off by any means which is in itself known, e.g. by solvent extraction and/or by distillation.
The process according to the invention makes it possible selectively to obtain meta-chloroanilines under conditions which are particularly advantageous for its industrial use, since the reaction is carried out in a completely homogeneous medium, without a catalyst and at very moderate pressures.
The examples which follow are given by way of indication, but without implying a limitation, in order to illustrate the invention. The degrees of conversion and the yields are molar ratios.
2,3,4,5-Tetrachloroaniline (0.1 mol) and an aqueous solution containing 8 mol/liter of hydriodic acid (50 ml) are introduced into a pressure-resistant tantalum-lined reactor of 200 cc capacity.
The mixture is heated for 16 hours at 135° C. under autogeneous pressure, with stirring.
After this reaction time, water and toluene (or monochlorobenzene) are added to the cooled reaction medium in sufficient amounts to give two clear liquid phases. These are separated by decantation and the iodine is removed from the aqueous phase by a series of extractions with toluene (or with monochlorobenzene). The organic phase is distilled under atmospheric pressure, which makes it possible to separate off virtually all the iodine from the polychloroanilines.
The organic residue is analysed by vapour phase chromatography.
Under these conditions, it is observed that the degree of conversion (DC) of the 2,3,4,5-tetrachloroaniline is 99.5% and the actual yield of 3,5-dichloroaniline is 61.1%; 37.5% of 2,3,5-trichloroaniline, formed as an intermediate, remains.
If this reaction is repeated with a heating time of 32 hours, the actual yield of 3,5-dichloroaniline is quantitative.
The procedure of Example 1 is followed with modification of the concentration of tetrachloroaniline (2,3,4,5-TTCA), the concentration of hydriodic acid (HI), the temperature (T) and the duration, hydrochloric acid (HCL) being added as the strong acid in two cases.
The table which follows gives the values of the parameters which vary, together with the degree of conversion of the 2,3,4,5-tetrachloroaniline and the actual yield of 3,5-dichloroaniline (3,5-DCA) and its intermediate 2,3,5-trichloroaniline (2,3,5-TCA). It should be noted that n is equal to 2 in this reaction.
If these experiments are repeated with twice the heating time, the actual yield of 3,5-dichloroaniline obtained is quantitative.
The procedure of Example 1 is followed, the 2,3,4,5-tetrachloroaniline being replaced by 2,3,5,6-tetrachloroaniline (0.05 mol) and the mixture being heated for 5 hours. It is found that, under these conditions, the degree of conversion of the 2,3,5,6-tetrachloroaniline is 96%, the actual yield of 3,5-dichloroaniline is 81.2%, and 14.7% of unconverted intermediate 2,3,5-trichloroaniline remains.
By following the above procedure but doubling the heating time, the degree of conversion of the tetrachloroaniline is 100% and the actual yield of 3,5-dichloroaniline is quantitative.
The procedure of Examples 2 to 7 is followed, the 2,3,4,5-tetrachloroaniline being replaced by 3,4,5-trichloroaniline, n being equal to 1 in this case.
The table which follows gives the values of the parameters which vary, together with the actual yield of 3,5-dichloroaniline.
By following the above procedure but doubling the heating time, the actual yields of 3,5-dichloroaniline are quantitative.
The procedure of Example 1 is followed, the 2,3,4,5-tetrachloroaniline being replaced successively by 3,4-dichloroaniline and 2,3-dichloroaniline, n being equal to 1 in these cases, each at a concentration of 2 mol/liter, the hydriodic acid being at a concentration of 8 mol/liter, the temperature being 135° C. and the duration being 5 hours.
Under these conditions, it is found that: 1/ the 3,4-dichloroaniline is converted to a degree of 48.4% and the yield of 3-chloroaniline is 91.5% relative to the 3,4-dichloroaniline converted; and 2/ the 2,3-dichloroaniline is converted to a degree of 37.5% and the yield of 3-chloroaniline is 88.2% relative to the 2,3-dichloroaniline converted.
2,3,5,6-Tetrachloroaniline (4×10-3 mol), liquid hydrogen iodide (16×10-3 mol) and 1,2,4-trichlorobenzene (20 ml) are introduced into a pressure-resistant tantalum-lined reactor of 200 cc capacity.
The mixture is heated under autogenous pressure for 2 hours at 170° and 210° C. respectively.
After this reaction time, it is found that: a/ at 170° C., the degree of conversion of the 2,3,5,6-tetrachloroaniline is 63.4%, the actual yield of 3,5-dichloroaniline is 57.2%, and 6.2% of unconverted intermediate 2,3,5-trichloroaniline remains; and b/ at 210° C., the degree of conversion of the 2,3,5,6-tetrachloroaniline is 84.1%, the actual yield of 3,5-dichloroaniline is 80.6%, and 3.5% of unconverted intermediate 2,3,5-trichloroaniline remains.
If these two experiments are repeated with double the heating time, the actual yield of 3,5-dichloroaniline obtained is quantitative.
2,3,4,5-Tetrachloroaniline (0.06 mol) and 2,3,5,6-tetrachloroaniline (0.06 mol) are introduced, together with 1,2,4-trichlorobenzene (100 ml), into a 250 cc glass round-bottomed flask. The mixture is stirred and heated to 160° C. When this temperature is reached, a stream of dry gaseous hydrogen iodide. is passed through at a rate of 18 to 20 g/hour, with stirring, the temperature being kept at 160° C.
The gaseous effluent is collected in a bubbler containing water.
The reaction is stopped after 4 hours 20 minutes by shutting off the stream of gaseous hydrogen iodide. 80.5 g of the latter have been used.
The mixture is then subjected to distillation under atmospheric pressure 1,2,4-trichlorobenzene (150 ml) being added progressively. It is thus possible to separate virtually all the iodine from the polychloroanilines produced by the reaction.
The contents of the reactor are then cooled and neutralised with a dilute aqueous solution of sodium hydroxide, and the organic phase is analysed by gas chromatography. It is found that the degree of conversion of the tetrachloroanilines is 99.5% and that the yield of 3,5-dichloroaniline is 98.1%. 0.9% of trichloroanilines, formed as intermediates in the conversion, remains.
1,2-Dichlorobenzene (100 ml), 2,3-dichloroaniline (0.168 mol) and 3,4-dichloroaniline (0.072 mol) are introduced into a 250 cc three-necked round-bottomed flask. The mixture is heated to 160° C. and gaseous hydrogen iodide (0.66 mol; i.e. 2.75 mol of HI per mol of DCA) is passed in over a period of 4 hours, the reaction mixture being stirred.
After this time, the reaction mixture is cooled and treated in a conventional manner (as described in the previous examples), and analysis by vapour phase chromatography shows that the degree of conversion of the dichloroanilines is 96.5% and the yield of 3-chloroaniline is 100% relative to the dichloroanilines converted.
The iodine formed is recovered quantitatively. The excess hydrogen iodide is also recovered in the form of iodine, after oxidation with hydrogen peroxide in an acid medium.
TABLE I __________________________________________________________________________ [2,3,4,5- No.Example mol/literTICA] mol/liter[Hl] ##STR3## mol/liter[HCl] °C.T hoursDuration TICADC % of 3,5-DCAAY % of 2,3,5-TCAADY % __________________________________________________________________________ of 2 2 8 2 -- 135 16 99.5 61.1 37.5 3 1 4 2 -- 135 5 97.6 19.1 78.5 4 1 8 4 -- 135 5 10.0 91.6 7.4 5 1 4 2 6 135 5 99.5 56.5 43.4 6 2 8 2 -- 163 1 98.0 57.2 36.5 7 0.5 2.4 2.4 7.6 163 1 100.0 81.8 13.6 __________________________________________________________________________
TABLE II __________________________________________________________________________ [3,4,5- No.Example mol/literTICA] mol/liter[Hl] ##STR4## mol/liter[HCl] °C.T hoursDuration BDC % of 3,4,5-TCAAY % of __________________________________________________________________________ 1 2 4 2 -- 135 16 70.5 70.5 10 2 6 3 -- 135 5 90.3 90.3 11 2 8 4 -- 135 5 98.0 98.0 12 2 8 4 -- 135 2 93.5 93.5 13 2 4 2 -- 163 1 69.5 69.5 14 2 4 2 4 163 1 78.0 78.0 15 2 8 4 -- 105 16 86.0 86.0 __________________________________________________________________________
Claims (15)
1. A process for forming a meta-chloroaniline B of the formula: ##STR5## wherein: X' and X" are each independently a hydrogen atom, a chlorine atom, an alkyl group containing from 1 to 4 carbon atoms or an alkoxy group containing from 1 to 4 carbon atoms, except that at least one of X' and X" is a chlorine atom; and
R', R" and R'" are each independently a hydrogen atom; a chlorine atom; an alkyl group containing 1 to 4 carbon atoms; an alkoxy group containing 1 to 4 carbon atoms; or phenyl, benzyl or phenoxy group, wherein the phenyl portion of said phenyl, benzyl or phenoxy is substituted by hydrogen or one or more halogen atoms, an alkyl group containing from 1 to 4 carbon atoms or an alkoxy group containing from 1 to 4 carbon atoms; except that at most two of R', R" and R'" are hydrogen atoms; which process comprises:
(1) forming a homogeneous liquid reaction mixture consisting essentially of:
(a) a polychloroaniline A of the formula: ##STR6## wherein: X', X", R' and R" are defined hereinabove, except that at least one of R', R" and R'" is a chlorine atom;
(b) hydrogen iodide in an amount sufficient to react with A according to the equation:
A+2nHI→B+nI.sub.2 +nHCl,
wherein n is an integer from 1 to 3, which represents the number of chlorine atoms to be removed per mole of polychloroaniline A; and
(c) a solvent; and
(2) maintaining said reaction mixture between about 90° to 250° C. thereby forming a reaction product containing said meta-chloroaniline B.
2. The process according to claim 1, wherein the molar ratio of the hydrogen iodide to the number of chlorine atoms to be removed per mol of the starting polychloroaniline A is between 2/1 and 20/1.
3. The process according to claim 1, wherein the molar ratio of the hydrogen iodide to the number of chlorine atoms to be removed per mol of the starting polychloroaniline A is between 2/1 and 10/1.
4. The process according to claim 1, wherein said solvent is an aqueous medium.
5. The process according to claim 1, wherein said solvent is an inert organic solvent.
6. The process according to claim 5, wherein the organic solvent is a chlorobenzene.
7. A process for forming a meta-chloroaniline B of the formula: ##STR7## wherein: X' and X" are each independently a hydrogen atom, a chlorine atom, an alkyl group containing from 1 to 4 carbon atoms or an alkoxy group containing from 1 to 4 carbon atoms, except that at least one of X' and X" is a chlorine atom; and
R', R" and R'" are each independently a hydrogen atom; a chlorine atom; an alkyl group containing 1 to 4 carbon atoms; an alkoxy group containing 1 to 4 carbon atoms; a phenyl, benzyl or phenoxy group, wherein the phenyl portion of said phenyl, benzyl or phenoxy is substituted by hydrogen or one or more halogen atoms, an alkyl group containing from 1 to 4 carbon atoms or an alkoxy group containing from 1 to 4 carbon atoms; except that at most two of R', R" and R'" are hydrogen atoms; which process comprises:
(1) forming a homogeneous liquid reaction mixture consisting essentially of:
(a) a polychloroaniline A of the formula: ##STR8## wherein: X', X", R' and R" are defined hereinabove, except that at least one of R', R" and R'" is a chlorine atom;
(b) hydrogen iodide in an amount sufficient to react with A according to the equation:
A+2nHI→B+nI.sub.2 +nHCl,
wherein n is an integer from 1 to 3, which represents the number of chlorine atoms to be removed per mole of polychloroaniline A;
(c) a solvent; and
(d) in the presence of a strong acid; and
(2) maintaining said reaction mixture between about 90° to 250° C. thereby forming a reaction product containing said meta-chloroaniline B.
8. The process according to claim 7, wherein the strong acid (d) is hydrochloric acid.
9. The process according to claim 1, wherein in Step (2) said reaction mixture is maintained at a temperature between about 110° and 220° C.
10. The process according to claim 1, wherein the autogenous pressure is equal to at most 100 bars.
11. The process according to claim 10 wherein said pressure is at most 50 bars.
12. The process according to claim 10 wherein said reaction is carried out in a stream of hydrogen iodide with continuous removal of the hydrogen chloride produced.
13. The process according to claim 1 wherein in the formulae A and B:
of X' and X", one is chlorine or hydrogen, and the other is chlorine; and
R', R" and R'" are chlorine or hydrogen, except that at most two of R', R" and R'" are hydrogen.
14. The process according to claim 13, wherein said meta-chloroaniline B is 3,5-dichloroaniline.
15. The process according to claim 13, wherein said meta-chloroaniline B is 3-chloroaniline.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8214682A FR2532305A1 (en) | 1982-08-24 | 1982-08-24 | PROCESS FOR THE PREPARATION OF METABLORINE ANILINES |
FR8214682 | 1982-08-24 |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US06518968 Continuation | 1983-08-01 |
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US4647700A true US4647700A (en) | 1987-03-03 |
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US06/780,212 Expired - Fee Related US4647700A (en) | 1982-08-24 | 1985-09-26 | Process for the preparation of meta-chloroanilines |
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US (1) | US4647700A (en) |
EP (1) | EP0102305B1 (en) |
JP (1) | JPS5959650A (en) |
KR (1) | KR890004781B1 (en) |
AT (1) | ATE14113T1 (en) |
BR (1) | BR8304556A (en) |
CA (1) | CA1209588A (en) |
DD (1) | DD210254A5 (en) |
DE (1) | DE3360353D1 (en) |
DK (1) | DK385683A (en) |
ES (1) | ES8404973A1 (en) |
FR (1) | FR2532305A1 (en) |
HU (1) | HU194156B (en) |
IL (1) | IL69370A (en) |
ZA (1) | ZA836150B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5051030A (en) * | 1990-06-05 | 1991-09-24 | Roy F. Weston, Inc. | Chemical detoxification process for treatment of soils contaminated with halogenated organic compounds |
US20110108486A1 (en) * | 2009-11-12 | 2011-05-12 | Schneider Charles A | Iodine extraction processes |
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CA2808258A1 (en) * | 2010-08-20 | 2012-02-23 | Lonza Ltd | Process for the selective meta-chlorination of alkylanilines |
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US4085141A (en) * | 1975-01-27 | 1978-04-18 | Bayer Aktiengesellschaft | Process for the preparation of anilines meta-substituted by chlorine |
US4206148A (en) * | 1977-09-22 | 1980-06-03 | Philagro | Process for the dehalogenation of halogen-containing aromatic compounds |
US4206147A (en) * | 1977-09-22 | 1980-06-03 | Philagro | Process for the dehalogenation of halogen-containing aromatic compounds |
US4329914A (en) * | 1974-12-17 | 1982-05-18 | Jydrpwatt Systems Limited | Cylinder-piston combination particularly for high-pressure application |
US4340759A (en) * | 1979-02-15 | 1982-07-20 | Rhone-Poulenc Agrochimie | Process for the preparation of anilines substituted by chlorine in the meta-position |
US4351959A (en) * | 1979-02-15 | 1982-09-28 | Rhone-Poulenc Agrochimie | Process for preparation of anilines substituted by chlorine in the meta-position |
US4418213A (en) * | 1980-08-01 | 1983-11-29 | Rhone-Poulenc Agrochimie | Process for the selective preparation of meta-chloroanilines |
US4429156A (en) * | 1980-11-08 | 1984-01-31 | Bayer Aktiengesellschaft | Process for the preparation of m-halogen-substituted anilines |
-
1982
- 1982-08-24 FR FR8214682A patent/FR2532305A1/en active Granted
-
1983
- 1983-07-29 IL IL69370A patent/IL69370A/en unknown
- 1983-08-11 AT AT83420139T patent/ATE14113T1/en not_active IP Right Cessation
- 1983-08-11 DE DE8383420139T patent/DE3360353D1/en not_active Expired
- 1983-08-11 EP EP83420139A patent/EP0102305B1/en not_active Expired
- 1983-08-19 ZA ZA836150A patent/ZA836150B/en unknown
- 1983-08-19 CA CA000434961A patent/CA1209588A/en not_active Expired
- 1983-08-23 JP JP58154021A patent/JPS5959650A/en active Pending
- 1983-08-23 ES ES525114A patent/ES8404973A1/en not_active Expired
- 1983-08-23 BR BR8304556A patent/BR8304556A/en not_active IP Right Cessation
- 1983-08-23 DD DD83254164A patent/DD210254A5/en unknown
- 1983-08-23 KR KR1019830003939A patent/KR890004781B1/en not_active IP Right Cessation
- 1983-08-23 DK DK385683A patent/DK385683A/en not_active Application Discontinuation
- 1983-08-24 HU HU832976A patent/HU194156B/en unknown
-
1985
- 1985-09-26 US US06/780,212 patent/US4647700A/en not_active Expired - Fee Related
Patent Citations (8)
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US4329914A (en) * | 1974-12-17 | 1982-05-18 | Jydrpwatt Systems Limited | Cylinder-piston combination particularly for high-pressure application |
US4085141A (en) * | 1975-01-27 | 1978-04-18 | Bayer Aktiengesellschaft | Process for the preparation of anilines meta-substituted by chlorine |
US4206148A (en) * | 1977-09-22 | 1980-06-03 | Philagro | Process for the dehalogenation of halogen-containing aromatic compounds |
US4206147A (en) * | 1977-09-22 | 1980-06-03 | Philagro | Process for the dehalogenation of halogen-containing aromatic compounds |
US4340759A (en) * | 1979-02-15 | 1982-07-20 | Rhone-Poulenc Agrochimie | Process for the preparation of anilines substituted by chlorine in the meta-position |
US4351959A (en) * | 1979-02-15 | 1982-09-28 | Rhone-Poulenc Agrochimie | Process for preparation of anilines substituted by chlorine in the meta-position |
US4418213A (en) * | 1980-08-01 | 1983-11-29 | Rhone-Poulenc Agrochimie | Process for the selective preparation of meta-chloroanilines |
US4429156A (en) * | 1980-11-08 | 1984-01-31 | Bayer Aktiengesellschaft | Process for the preparation of m-halogen-substituted anilines |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
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US5051030A (en) * | 1990-06-05 | 1991-09-24 | Roy F. Weston, Inc. | Chemical detoxification process for treatment of soils contaminated with halogenated organic compounds |
US20110108486A1 (en) * | 2009-11-12 | 2011-05-12 | Schneider Charles A | Iodine extraction processes |
US9994448B2 (en) * | 2009-11-12 | 2018-06-12 | Iofina Chemical, Inc. | Iodine extraction processes |
Also Published As
Publication number | Publication date |
---|---|
DK385683D0 (en) | 1983-08-23 |
FR2532305B1 (en) | 1984-12-07 |
IL69370A0 (en) | 1983-11-30 |
HU194156B (en) | 1988-01-28 |
JPS5959650A (en) | 1984-04-05 |
FR2532305A1 (en) | 1984-03-02 |
EP0102305B1 (en) | 1985-07-03 |
DE3360353D1 (en) | 1985-08-08 |
EP0102305A1 (en) | 1984-03-07 |
ZA836150B (en) | 1984-04-25 |
DK385683A (en) | 1984-02-25 |
KR890004781B1 (en) | 1989-11-27 |
CA1209588A (en) | 1986-08-12 |
IL69370A (en) | 1988-01-31 |
KR840006193A (en) | 1984-11-22 |
DD210254A5 (en) | 1984-06-06 |
ES525114A0 (en) | 1984-05-16 |
ES8404973A1 (en) | 1984-05-16 |
BR8304556A (en) | 1984-04-03 |
ATE14113T1 (en) | 1985-07-15 |
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